Angelfish require a pretty minimum tank set up for spawning. A bare bottom, fairly tall tank (20 gallon tall), piece of slate and a sponge filter are the usual recommendations. No hang on tank filters as the fry will be sucked up into it. Plenty of places to look up information on angelfish breeding on the net. Check out my reference for a slew of facts about fresh water fish.Without the above, though, a breeding pair will continue to spawn, just unsuccessfully. The eggs won't mature or will get picked off by scavengers or other fish. The angels will, though, continue to do their thing. I have a pair of pure black 6 inch breeders which I do not breed at this time. Doesn't stop them from spawning.
Good luck.